SIMILAR POLYGONS : SIMILAR POLYGONS BY: MR. EMERSON R. RESPONZO
FACULTY
UNIVERSITY OF LA SALETTE
HIGH SCHOOL DEPARTMENT
MALVAR, SANTIAGO CITY
S. Y. 2009-2010
OBJECTIVE: : OBJECTIVE: To identify and apply the properties of similar polygons
Can you still remember the congruent object/figures? : Can you still remember the congruent object/figures? Congruent figures have the same shape and size
Look at the following: : Look at the following: A B C D Similar figures have the same shape but not necessarily the same size
Slide 5: Definition: Two polygons are SIMILAR – if their corresponding angles are congruent and the lengths of their corresponding sides are in proportion. Symbol ~
Slide 6: Trapezoid ABCD ~ trapezoid EFGH A B C D E F G H What are the corresponding angles? What are the corresponding sides? 8 8 12 16 12 6 6 9
Slide 7: Are the polygons similar? Yes or no? A B C 6 8 10 x D E F 9 12 15 x YES NO
Slide 8: Sorry this is not the correct answer
Slide 9: Congratulations!
You are correct!
Slide 10: Are the polygons similar? Yes or no? A B C 6 8 11 x D E F 9 12 15 x YES NO 150 150
Slide 11: Sorry this is not the correct answer
Slide 12: Congratulations!
You are correct!
Slide 13: Name the corresponding angles.
Write the proportion for the lengths of the corresponding sides.
Give the scale factor, first to second. H I J K L M N O P Q 12 10 4 4 x 12 18 6 6 15 Given that they are similar:
Slide 14: Lets try to answer the following:
Given that the following pairs of polygons are similar give a similarity statement, the scale factor and find the missing lengths. A B D C E F H G 20 15 25 9 6
Slide 15: QUIZ Given that the following pairs of polygons are similar give a similarity statement, the scale factor and find the missing lengths. G O T M A N 40 36 27 18
TRUE OR FALSE : TRUE OR FALSE All squares are similar.
All rectangles are similar.
If two triangles are isosceles, then they are similar.
If two polygons are regular, then they are similar.
If two polygons are similar, then they are congruent.
If two polygons are congruent then they are similar